Improved automatic friction dog lathe-chuck



i Figure-3 represents a vertical section on line A B,

dial sliding blocks ani `ble adjusting screw, as` ereinafter describe "Third, in the combination with the lathe-chuck, ra-

y `LcnnNe cons, or WORCESTER, IMasskonusnr'rs.`

@wat Gettin.

r@Letters Patent No, 103,015, date'd'ili'fl'y 17, 1870.

ilvi'pnoynn AUTOMATIC rRIcTIoN DOG LATER-CHUCK.

The Schedule referred to .'mnthesel Letters Patent andmaking part of the same To all whom it "mag/,concerns Be iit known that 1, LORING GOES, of thecity and county` of Worcester,and Commonwealth of Massachusetts,'l1ave invented certain new and useful improvements in AutomaticFriction Dog Lathe- Chucks; and Ido `hereby declareythat the following 'is a full, clean-and exact description of the same, `ret'erence'beirlg had `to the accompanying drawings forming a part of this speciication",` in'whichiFigure l represents a-sidc ,view of my vautomatic friction dog lathechnck;` i

` Figure 2 represents a front view ot' the same;

lig. 2;.and w W i i Figure 4 represents acentra-l section on line -G D,

' To enable those skilled in the art to` which my inceed to describe it more in detail. 4

The nature of myinventiou consists- Firstin vthe arrangement, upon the body` of the lathe-chuck,`0,i" radial fslidingblocks, and, upon the said` hlockspeccentricyclamp-dogs, substantially as hereinafter describedin virtue ot'` which" said dogs i f ventionbelongs to` make andusethe same, I will promay be made topper-ate conjointly, and grasp the rod placed betweenthe ou opposite sides. tion, with the lathe-chuck, ra-

n "icclamp-dogsf a dou- Second,in the com dial .sliding blocks', eccentric clamp-dogs,.and double `adjusting screw, of a centering spring, as hereinafter described. i i Fourth, in4 the 4combination with the "body of the lathe-chuck and eccentric clamp-dogs, of a friction- 'disk and return spring, for operating said dogs, `as

hereinafter described.` y

Fifth, in thecombination with the friction disk and i eccentric`clampdogs,cf starting tugs and aretnrn thechan'nel ,in such-a manner that the slide blocks D sircd. A ,4 p

l Projections@ are formed at one side ot' the slide` are retained firmly to thei body A, but can he moved radially in the said i grooves 'from the center .tgwagd the circumfer ce of `the chuck, and 'vice refrsa, asdi the drawings.

blocks D, through which is arranged a double adjust- 'ing screw, F, having, at one end, afright-hand thread, `b, and, at the other, a left-hand thread, c, so that spring G works in an angular grci'e around the cen-` tral part of the screw F, and the action ofthe spring keeps the slide blocks -D in the properrelativevposition, as regards the'center -ot the chuck, when said y blocks are in any adjusted position.

Clamp-dogs H are pivted .on screws or bolts I to the outer iside oi' the slideblocks D, as indicated in Tile faces e of the dogs H are formed on' curves eccentric to their pivot centers, so that when saiddogs are swung back, the distance between theface f Aone and the other is greater than when they are swung forward to the position indicated in the drawings,

thereby forming eccentric clamps, between which a round bar of iron or otherfmaterial may be firmly held. The curved .faces eare serrated or notched parallel with the axis of the spindles, to prevent them from slipping whenused on smooth surfaces.

A frictionY disk, J, is hung upon the liubiBot the chuck at the back partthereof, and secured by means of `an annular plate, f, which is secured by screws g to the rear end of the hub B, with its `edgefproject ing over the edge of the disk J, as indicated in tig, 4 of the drawings..

The disk J is allowed to turn upon the hub, and a volute spring, K, is arranged between said disk and the body A of the chuck,and the expansive force of the spring K tends to keep the disk J in the position shown in the drawings. g l c -Lugs L L M M are formed on the disk 'J foroper ating the dogs H, the shanks, N, of which `'extend past the ends of the slide blocks D, andfback far venough to be acted upon by the lugs L and M whenl the disk J is turned on the' hub B o't' the chuck. .lhe lugs L and M, being--arrangedateither side of the Shanks N, prevent the disk J from turning any further than' is necessaryv to operate the dogs'H, and said lugs are placed at some distance apart, so that they will strike the'shankswith a shockisimilarto ablow from a hammer, the `'more readily to'stait the dogs in case theyare clamped very -firmly upon thework.

The disk J may be operated by means of a friction band applied Yto vitsperiphery, and worked by vrthe footV posing the lathe to be in motion, the chuck revolving in the direction indicated by the arrow, and it is desired to place a round bar of iron in the chuck, the

operation is as follows:

The operator places his foot upon the treadle or stirrup of the friction device, which presses the band or pad upon the disk J with sufficient force to counteract the force of the return spring K, and thereby retard the motion of the disk J, when the Shanks of the dogs H, which are carried forward by the body of the chuck, are brought in contact with the lugs M with sufficient force to swing back the dogs H to the position shown in dotted lines, iig. 1. The operator then places the end of the bar of iron upon the center point and removes the friction from the disk J, which latter is immediately thrown forward by the return spring K, bringing the lugs L in contact with the shanks N, and thereby swinging forward the dogs H, lwhich clamp the bar of iron between their curved faces c, where it is firmly held during the operation of turning.

The eccentric faces of the dogs H act in opposition to the turning tool in such a manner that the greater the resistance upon the bar the more firmly will itbe clamped by'the dogs H.

To remove the bar from the lathe, the operator applies the friction to the disk in the manner before described, and the shanks N, coming in contact with the lugs M, throw back the dogs H. The momentum acquired while the shanks N are passing across the space .between the lugs L and M produces a shock when the shanks strike the latter, sufficient to loosen their clamping faces c from the bar to which they are clamped.

Thus it will be seen that the ywork may be readily placed in the lathe and removed, therefrom without stopping the motion of the spindle, thereby saving much time and labor.

In lieu of making the chuck with a rim, C, around the body A, the rim I of the friction disk J may be made broad enough to cover both parts, and the lugs L .WI may be formed upon said rim, if preferred.`

lhe eccentric clamp-dogs H H may, if desired, be pivoted directly to the body A of the chuck.

It will be apparent to thoseskilled in the art to which my invention belongs, that the chuck is well adapted for holding irregular shaped bars or pieces of material as well as those of cylindrical form.

The body of the chuck may be made in a diierent form, if desired, and I contemplate making it in rectangular form for very large and heavy work, in which case, however, a hand-lever will have to be used for operating the eccentric dogs. I also contemplate making the sliding blocks D wide enough to permit of `the adjusting screw passing through the main part of the blocks, thus dispensing with the side projections E. Instead ot' a single centering spring G, two may be employed, one combined with each sliding block, although I prefer the arrangement shown in the drawings.

Having described my improved automatic friction dog lathe-chuck,

What I claim therein as new and of my invention, and desire to secureby Letters Patent, is-

1. The arrangement, upon the body of the chuck, of the radial sliding blocks, and upon said blocks the two eccentric clamp-dogs, substantially as described, in virtue of which said dogs may be made to operate conjointly and grasp the rod placed there, on opposite sides, asset forth.

2. The combination, with the chuck-body A, radial sliding blocks D, and eccentric clamp-dogs H, of the adjusting-screw F,-as herein shown and described.

3. The combination, with the chuck-body A, the radial sliding blocks D, the eccentric clamp-dogs H, and the double adjustingscrew F, of a centering spring G, substantially as and for the purposes set forth.

4. The combination, with the chuck A and eccentric clamp-dogs H H, of the friction disk J and return spring K, substantially as and for the purposes set forth.

5. The combination, with the friction disk J and eccentric clamp-dogs H H, of start-ing lugs L L and M M, and spring K, substantially as and for thepurposes set forth.

LORING GOES.A

"itnessesz Taos. H. Denen, A. E. Printen. 

